Field of the Invention
The invention relates to an oven muffle having an insulation layer contained in an interstice provided between two insulating walls.
In the following, the term oven muffle is to be generally understood as a muffle of any household appliance which requires insulation. For thermal insulation of oven muffles, glass wool or mineral wool fibers are conventionally used. However, these glass wool or mineral wool fibers are increasingly being replaced for health and safety reasons. Granulates, as used for instance in accordance with Published German Patent Applications DE 40 28 743 A1 or DE 195 29 040 A1 in oven muffles of the type defined above, have the tendency of being compressed or reduced in size during use of the oven muffle. This is caused by motions of the muffle wall and the outer wall defining the muffle wall. These motions are due to temperature changes and cause a loss of volume of the insulation material which results in poor insulating properties.
As alternatives, organic binding agents, the use of which should however be avoided, or the use of mats or slabs of composite material, which may include foils, foam and the like, has been suggested for instance in accordance with Published German Patent Application DE 44 38 294 A1.